Yusimy Men's Heated Vest Dual-ControlHeating Stand-Up Collar Zip-Front USB Rechargeable Warm Tech-Style Vest

This vest does not have the 28 or whatever heating zones. There is like a 6x6 inch pad in the back that maybe has two or three heat points, one on each shoulder and neck, and two in the front each on the pocket. If you can imagine it, it is more like an electrode and it just radiates heat. At full power the vest runs at approximately 18-19 watts. 5 volts at 1.8 amps. I ordered a medium and it turned out to be small. I ordered another model in medium from another seller and got a large. There is a lot of irregularity regarding size with these vendors. I recommend to order a few different sizes even and make a return of the ones that don't fit because how else are you supposed to match your size?